From the given options 64 units is the area of square that Margo used. So, option D is correct.
SOLUTION:
Given, Margo draws a triangle. The lengths of the sides of the triangle are
![8^(\prime \prime), 15^(\prime \prime) \text { and } 17^(\prime \prime)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ykkm20sehey388tz9c63dpcvtdqux2ubif.png)
Margo uses the area of 3 squares to show that the triangle is a right triangle. We have to find the area, in square units, of a square that Margo uses . Now, we know that, we can prove a triangle as right angled triangle using Pythagoras theorem
![\text { Pythagoras theorem } \rightarrow \text { hypotenuse }^(2)=\text { side }^(2)+\text { side }^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6wgk8acdswm24h95unxrdbpky92444mwzz.png)
Assume that above theorem is equation of area of one square = sum area of two squares. Then, using area of three squares we can prove that a triangle is a right angle triangle.
Now, areas of the three squares will be
![8^(2), 15^(2), 17^(2) \rightarrow 64,225,289](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7uj1iq1s0ruhxcs6m4p0g6fpx9kxlyfeoc.png)